Well their are four essential components to make a combustion engine run. They are:
1. Fuel
2. Air
3. Spark
4. Compression

If anyone of these is missing the car won't run. How was the car running before this? Did this problem occur suddenly?

If you have never changed your fuel filter, spark plugs or cleaned your Idle Control Valve (ICV) now would be a good time. The fuel filter can get clogged up and effect the mount of fuel going to the engine.

Now, one thing to also look t that is really important: how are all your vacuum lines? Check all your hoses and connections for either a lose hose or a crack or tear in the hose. A vacuum leak has been known to make cara run poorly. Vacuum lines are cheap too if it is damaged. But go get a good light and inspect them all. A crack may be very hard to see so look carefully and feel them too. If you need assistance the Bentley Service Manual has some excellent pictures and instructions to help you.